Radically polymerizable composition resulting in shock resistant organic lenses

ABSTRACT

A radically polymerizable composition comprising:
         a first component A comprising at least an oligomer having at least two radically polymerizable functions and the homopolymer of which has a glass transition temperature (T g ) lower than 50° C., such a component being able to result through polymerization in a (co)polymer having a glass transition temperature (T g ) equal to or lower than 50° C., preferably equal to or lower than 0° C. and more preferably ranging from −50° C. to −10 C., said oligomer accounting for more than 15%, preferably at least 20% of the total weight of the polymerizable monomers present in the composition; and   a second component B comprising at least a (meth)acrylic monomer having at least one H link promoting group, such a (meth)acrylic monomer accounting for at least 15% of the total weight of the polymerizable monomers and oligomers present in the composition when such a monomer is a methacrylic monomer and at least 35% of the total weight of such polymerizable monomers and oligomers present in the composition when such a monomer is an acrylic monomer.

This application is a national phase application under 35 U.S.C. § 371of International Application No. PCT/FR02/04050 filed 26 Nov. 2002,which claims priority to French Application No. 01/15273 filed 26 Nov.2001, the entire contents of both of which applications are incorporatedherein by reference.

The invention generally relates to thermally photopolymerizable and/orpolymerizable compositions, depending on the primer type being used forthe reaction, resulting in transparent lenses, more particularlyophthalmic lenses, with a good shock resistance.

One of the best known organic lenses used for its excellent shockresistance properties is bisphenol-A polycarbonate, commonly referred toas PC, and the derivates thereof. Such a lens, being a thermoplasticmaterial, is fully satisfactory for the wearer and can be produced ateconomical costs through injection by using injection moulding machines,perfectly well adapted to mass production.

When these are so-called prescription lenses, i.e. manufactured ondemand depending on the correction to be applied to the lens wearer'seyesight, a previously injected semi-finished lens is being used, oneface thereof already having its definitive geometry and the second facebeing then surfaced, followed by polishing operations using appropriatetools.

Polyurethane-polyurea based shock resistant material lenses haverecently been marketed under the trade name TRIVEX®. The method forobtaining such lenses is disclosed in U.S. Pat. No. 6,127,505.

Other materials from the same chemical family, but incorporating sulphurto increase the refractive index, are disclosed in International PatentApplications WO 01/36.507 and WO 01/36.508.

Such materials are obtained through polycondensation by means of atricky to implement method.

European Patent Application EP 1,035,142 discloses the polymerization ofan acrylic copolymeric material for obtaining ophthalmic itemscomprising polymerisation of at least one α,β-ethylenically unsaturatedcarboxylic acid and of at least one aryl(meth)acrylate monomer in thepresence of a cross-linking agent. The cross-linking agent, optionallyaccounting for 0.5 to 15% in weight of the total weight of the monomerspresent in the composition, more particularly comprises ethyleneglycoldimethacrylate, diethyleneglycol dimethacrylate, polyethyleneglycoldimethacrylate, allyl methacrylate, 1,3-propanediol dimethacrylate,allyl methacrylate, 1,6-hexanediol dimethacrylate, 1,3-butanedioldimethacrylate, 1,4-butanediol dimethacrylate, as well as divinylcompounds including divinyl hydrocarbons and divinyl benzene.

The examples in said Patent Application only mention the use, as across-linking agent, of ethyleneglycol dimethacrylate or 1,3-butanedioldimethacrylate.

The article by Robert A. SCOTT and Nicolas A. PEPPAS <<Compositionaleffects on network structure of highly cross-linked copolymers ofPEG-containing multiacrylates with acrylic acid >> discloses aphotopolymerisable composition containing PEG 400 diacrylate and 23.6%in weight of acrylic acid.

It would therefore be desirable to provide a radically polymerizablecomposition, more particularly through photopolymerization, resulting ina polymeric material having a high shock resistance, goodthermomechanical properties, a low water absorbency and able to be usedfor manufacturing transparent substrates, in particular optical itemssuch as ophthalmic lenses.

The above-mentioned technical problems are overcome according to thepresent invention by a radically polymerizable composition comprising:

-   -   a first component A comprising at least an oligomer bearing at        least two radically polymerizable functions and the homopolymer        of which has a glass transition temperature (T_(g)) lower than        50° C., such a component A being able to bring through        polymerization to a polymer having a glass transition        temperature (T_(g))<50° C., preferably equal to or lower than        0° C. and preferably ranging from −50° C. to −10° C., the        oligomer of the component A accounting for more than 15%,        preferably at least 20% of the total weight of the polymerizable        species present in the composition; and    -   a second component B comprising at least one (meth)acrylic        monomer having at least one H link promoting group, such a        (meth)acrylic monomer accounting for at least 15% of the total        weight of the polymerizable species present in the composition        when such a monomer is a methacrylic monomer and at least 35% of        the total weight of such polymerizable species when such a        monomer is an acrylic monomer.

Preferably, the oligomer of component A is a difunctional compound.

Generally, the oligomer of component A has a number average molecularmass ranging from 100 to 5,000, preferably from 200 to 4000, morepreferably from 300 to 2,000 g.mol⁻¹.

The oligomer of the first component A is preferably selected amongstpoly(alkylene)glycols di(meth)acrylates, polyethoxy bisphenol-Adi(meth)acrylate, dithio(meth)acrylate oligomers and urethanedi(meth)acrylates, thiourethane di(meth)acrylates and di(meth)acrylatepolysulfides.

The preferred polyalkyleneglycol di(meth)acrylates arepolyethyleneglycol and polypropyleneglycol di(meth)acrylates, moreparticularly polypropyleneglycol di(meth)acrylates and mostparticularly, polypropyleneglycol dimethacrylates.

The preferred dimethacrylate oligomer is a polypropyleneglycoldimethacrylate with a number average molecular mass of about 530 g.mol⁻¹(PPG 400 DMA) marketed under the designation SR644OP by CRAY VALLEYCorporation.

Such polyethylene- or polypropyleneglycol di(meth)acrylate oligomerssuitable for the present invention can be represented by the followingformula:

wherein R¹ and R² represent H or CH₃, A represents a divalent moietywith the formula:

where m₁, m₂ and m₃ are each an integer ranging from 4 to 20.

When several oligomers (I) are used admixed together, a mean value canbe defined:

$\overset{\_}{m} = {\sum\limits_{m = 4}^{20}{X_{m} \cdot m}}$wherein X_(m) is the weight ratio of the oligomer (I) for which Acomprises m ethylene- or propyleneglycol patterns in its chain based onthe total weight of the oligomers with formula (I) of the blend.

When as the first component A of the invention, commercial products areused that are already oligomer blends, such a value m is easily obtainedperforming a HPLC analysis of the blend t calculating the report:

$X_{m} = \frac{S_{m}}{S_{total}}$where S_(m) represents the surface of the peak corresponding to themonomer (I) comprising m propyleneglycol patterns in the divalent moietyA, and S_(total) represents the total surface of all the peakscorresponding to the monomers (I) for which m ranges from 4 to 20.

According to the invention, blends of several polymers (I) arepreferably used for which the mean value m such as defined hereinaboveranges from 5 to 10, preferably from 6 to 9.

However, it is possible to use blends of several oligomers (I) for whichthe mean value is higher than 20 and preferably ranges from 30 to 40.Calculating the mean value occurs as hereinabove, but for all theoligometric fractions, including of course for the oligomers (I) forwhich the value m is higher than 20. A commercially available oligomerexists for A=propoxy and m=32.

Still preferably, the monomers (I) have a branched structure, i.e. thedivalent moiety A represents:

m₃ having the meaning as previously indicated.

The monomers (I) are commercially available from CRAY VALLEY Corporationunder the commercial designations SR⁶⁴⁴OP, CD644OP and from SHINNAKAMURA Corporation under the commercial designation 9PG and from theUCB Corporation under the commercial designation PPG400.

SR6440P is a blend of several monomers (I) the central pattern is asfollows:

with m₃ as an integer having values ranging from 3 to 10 according tothe following mass ratios:

m₃ = 3  2% m₃ = 4  8% m₃ = 5 14% m₃ = 6 20% m₃ = 7 27% m₃ = 8 19% m₃ = 9 9% m₃ = 10  1%with a mean value m ₃=6.6.

Another di(meth)acrylate oligomer class suitable for the component A ofthe composition according to the invention includes the polyalkoxy(preferably ethoxy or propoxy) bisphenol-A dimethacrylates having from10 to 80 alkoxy patterns (in mean value).

Amongst such bisphenol-A di(meth)acrylate compounds are to be mentionedthe compounds represented by formula (II):

where R¹ and R² represent, independently from each other, H or CH₃, Xrepresents —(CH₂—CH₂—O)—, —(CH₂—CH₂—CH₂—O)— or —(CH₂—CHCH₃—O)—,preferably —(CH₂—CH₂—O)—,-and n₁+n₂ has a mean value ranging from 10 to50, preferably from 10 to 40.

Preferred compounds represented by the above-mentioned formula are thosefor which R¹=R²=CH₃, X═—CH₂CH₂0—, and n₁+n₂=10 or n₁+n₂=30.

Preferred ethoxy bisphenol-A di(meth)acrylate oligomers are bisphenol-Adimethacrylate with 30 ethoxy patterns (BPA30EODMA) marketed under thedesignations BPE-1300N by SHIN NAKAMURA CHEMICALS and SR 9036 by CRAYVALLEY Corporation, bisphenol-A dimethacrylate with 32 propoxy patterns,bisphenol-A diacrylate with 32 propoxy patterns and bisphenol-Adiacrylate with 16 propoxy patterns.

The most preferred bisphenol-A oligomer is BPA30EODMA.

The oligomer of component A of the compositions according to theinvention could also be a di[thio(meth)acrylate], i.e. an oligomericcompound containing two functions:

with R=H or CH₃more particularly, a dithiomethacrylate represented by the formula:

where n is an integer ranging from 1 to 10, or a blend of suchdithiomethacrylates.

The oligomer of the component A could also be an urethanedi(meth)acrylate. In particular are to be mentioned the aliphaticurethane diacrylates marketed by CRAY VALLEY Corporation under thedesignations CN934, 935, 965, 963, 966, 967, 981 and by UCB Corporationunder the designations EBECRYL 230, 244, 245, 270, 284, 285, 4830, 4835,and 8800 and the aromatic urethane diacrylates marketed by CRAY VALLEYCorporation under the designations CN 970, 972, 973 and 976 and UCBCorporation under the designations EBECRYL 210, 215 and 4244.

When the oligomer of component A is an urethane di(meth)acrylate, highamounts of components B are preferably used (at least 40% in weight ofthe polymerizable species present in the composition).

Component A of the compositions of the invention could additionallycomprise at least one other comonomer, being not an oligomer, comprisingat least one radically polymerizable function and, preferably, tworadically polymerizable functions.

The preferred comonomers for component A are mono- or di(meth)acrylatecomonomers such as alkyl(meth)acrylates such as methyl(meth)acrylate andethyl(meth)acrylate; cycloalkyl(meth)acrylates such ascycloethyl(meth)acrylate and dicyclopentyl(meth)acrylate;aryl(meth)acrylates such as phenyl(meth)acrylate, benzyl(meth)acrylate;naphthyl(meth)acrylates; phenoxyalkyl(meth)acrylates such asphenoxyethyl(meth)acrylate and phenoxybutyl(meth)acrylate;alkyleneglycol dimethacrylates such as ethyleneglycol di(meth)acrylateand propyleneglycol di(meth)acrylate.

Other comonomers include vinyl or polyvinyl compounds as well as allylor polyallyl compounds such as divinylbenzene.

However, selecting such comonomers should occur so that the firstcomponent A brings, through polymerization, to a polymer or copolymerwith a glass transition temperature Tg equal to or lower than 50° C.

The second component B is preferably a monofunctional compound and moreparticularly a compound represented by the formula:CH₂═C(R)—Z—Z′  (IV)wherein R represents H or CH₃, Z represents a single covalent link or aspacer group.

Z is preferably a divalent hydrocarbon chain, optionally interrupted byone or more heteroatoms, preferably selected amongst O, S, N or by oneor more groups as follows:

by one or more divalent groups selected amongst:

-   —NH—CO—NH—-   —NHCOO—-   —NHCOS—-   —NHCSS—.

Still preferably, the hydrocarbon chain is a short chain and comprisesfrom 1 to 10 carbon atoms and more preferably from 1 to 6 carbon atoms.

As an example, the spacer group Z could be a polyether, polyester,polyurethane, polyurea, polythiourethane group.

Z′ is a monovalent short chain, preferably comprising from 1 to 10carbon atoms, and more preferably from 1 to 6 carbon atoms and includesat least one H link promoting group selected amongst the groups:

-   —COOH-   —OH-   —CONHR′-   —NHCONHR″-   —NHCOOR′″-   —NHCOSR^(iv)-   —NHR^(v)    where R′, R″, R′″, R^(iv), R^(v) represent, independently from one    another, H or an alkyl with from 1 to 10 carbon atoms or aryl with    from 6 to 10 carbon atoms.

The alkyl group could be itself aliphatic or cycloaliphatic.

Preferably, the alkyl group represents represents CH₃.

Preferably, Z′ represents a H link promoting group selected amongstCOOH, OH and CONHR′ groups, preferably a COOH group.

Preferably, R is CH₃.

The H link promoting group in the compound with formula IV could alsobe, on its own, a carbonyl function and/or a tertiary amine function. Insuch a case, both those functions interact with the above-mentionedfunctions for Z′ and all comprising a polar link of the X—H type (X═O,S, N . . . ) for forming hydrogen links. The carbonyl and tertiary aminefunctions could therefore be used as a complement of the above-mentionedH link promoting functions.

The preferred monofunctional monomers having hydrogen link precursorgroups are methacrylic acid (AMA), acrylic acid (AA) and (meth)acrylicmonoesters of carboxylic diacids such asmono-2-(methacryloyloxy)ethylsuccinate (MA succinate) represented by theformula:CH₂═C(CH₃)CO₂CH₂CH₂O₂CCH₂CH₂CH₂CO₂H  (a)and mono-2-(methacryloyloxy)ethylphthalate (MA phthalate) represented bythe formula:2—[CH₂═C(CH₃)CO₂CH₂CH₂O₂C]C₆H₄CO₂H  (b)

Preferably, component B is methacrylic acid.

Still preferably, components A and B are only methacrylic compounds.

The compositions according to the invention also comprise apolymerization priming system. The polymerization priming system couldcomprise one or more thermal or photochemical polymerization primers.Such primers are well known in the art and any conventional primer couldbe used. Amongst such thermal polymerization primers useful in thepresent invention are to be mentioned peroxides such as benzoylperoxide, cyclohexyle peroxydicarbonate and isopropyl peroxydicarbonate.

Amongst the photoprimers are to be mentioned, more particularly,2,4,6-trimethylbenzoyldiphenylphosphine oxide,1-hydroxycyclo-hexylephenylketone, 2,2-dimethoxy-1,2-diphenylethan-1-oneand alkyl benzoyl ethers.

In general, primers are used in a proportion ranging from 0.01 to 5% inweight based on the total weight of the polymerizable monomers containedin the composition.

The polymerizable compositions according to the invention could alsocomprise additives conventionally used in polymerizable compositions formoulding optic or ophthalmic items, in particular glass lenses andlenses, in the conventional proportions, i.e. release agents,inhibitors, dyes, UV absorbers, perfumes, deodorizing agents,antioxidants, anti-yellowing agents and photochromic compounds.

The use of H link promoting component B has the advantage to stiffen thevery flexible network formed by component A, without, however,introducing a too high cross-linking density which would be detrimentalto the shock resistance of the final material. Thus, the polymerizedmaterials according to the invention have the required thermo-mechanicalproperties, i.e. a good stiffness at 25° C., which is the usetemperature for the lenses, and at 100° C. which is the temperaturereached at various steps of the method for manufacturing the glass andupon subsequent processings (coloration, polishing). The materialsobtained from the compositions according to the invention have anelastic modulus (E′) at 100° C. of at least 40 MPa, preferably 100 MPaand more preferably of at least 120 MPa, or most preferably 150 MPa.

Preferably, the compositions according to the invention arephotopolymerisable compositions and the materials obtained through thepolymerization of compositions according to the invention are preferablyorganic lenses obtained through conventional moulding, preferablythrough photopolymerization.

As previously indicated, the lens could be a semi-finished lens, that isthat one face thereof is still to be surfaced into its final geometry,but obviously, the method could equally apply to manufacturing afinished lens, i.e. comprising both optical faces at the requiredgeometry at the end of the moulding operation.

A finished lens can thereby be obtained at the shortest notice throughphotopolymerization using conventional photopolymerization devices, in amuch easier way to implement and to control than in the case of apolycondensation.

The resulting lenses have an excellent shock resistance as well as avery low water absorption.

The following examples illustrate the present invention. In theexamples, unless otherwise indicated, all the percentages and parts arein weight.

EXAMPLE 1

60 g of BPA30EODMA are mixed with 40 g of methacrylic acid at roomtemperature. Mixing is performed, 0.1 g of CGI 819® is added (phosphineoxide photoprimer from Ciba). The composition is obtained in a room witha controlled lighting in a smoky glass vial.

The thus prepared composition is cast into a mould in two mineral glassparts previously cleaned with soda, parallely assembled by means of aBamier adhesive tape and two millimetre apart.

Casting occurs as follows:

-   -   the composition is taken out using a sterile syringe (20 ml);    -   the adhesive tape is partially dismantled so as to create an        opening;    -   the tip of the syringe is inserted into the opening;    -   the composition is injected into the mould; and    -   the adhesive tape is replaced in order to sealingly close the        mould.

The filled mould is then put in a photochemical polymerization ovencomprising two UV prima lamps (mercury lamps) arranged on both sides atequal distance of the mould parts, the mould receiving from each lamp anillumination of approximately 40 milliwatt for 30 seconds.

The infrared measurements allow to follow the conversion of double(meth)acrylic links as a function of the UV irradiation time. After 30seconds of irradiation, the conversion is completed.

After polymerization, the adhesive tape is removed. The lenses are thenreleased and then checked with an arc lamp.

A final annealing operation at 120° C. allows to bring thepolymerization to completion and to release the residual constraints ofthe resulting substrate.

The results are indicated in table 1 hereinbelow.

COMPARATIVE EXAMPLES C1 AND EXAMPLES 2 to 4

Example 1 is repeated varying the methacrylic acid and BPA 30EODMAproportions. The proportions of the starting components as well as theresults are indicated in table 1 hereinbelow.

Comparative example C1 comprises BPA30EODMA as polymerizable monomer.

TABLE I C1 EX1 EX2 EX3 EX4 Polymerizable composition (liquid) BPA30EODMA (%) 100 60 50 45 70 AMA (%) 0 40 50 55 30 Release agent¹ (%) 0 00.1 0.1 0.1 UV absorber² (%) 0 0 0.07 0 0 Photopolymerization primer³(%) 0.1% 0.1% 0.1% 0.1% 0.1% n_(D) (25° C.) 1.491 1.470 1.464 1.4601.456 Density — — 1.08 1.06 — Solid polymerized material n_(e) (25° C.)— 1.516 1.518 1.515 1.517 ν_(e) (25° C.) — 48 49 55 53 Density 1.16 1.231.25 1.25 1.26 E′ at 25° C. (MPa) — 1,600 3,560 4,000 4,500 E′ at 100°C. (MPa) — 140 1,300 1,600 2,200 Tg (° C.) −30 40 — 160 >160 ¹ZELECUN(lubricant from DUPONT CHEMICALS) ²UV 5411:2-(2-hydroxy-5′-t-octylphenyl)benzotriazole from AMERICAN CYANAMIDCorporation ³CGI 819 ® from CIBA GEIGY Corporation (The amounts ofrelease agent, UV absorber and photopolymerization primer are indicatedin % based on 100 parts in weight of components A and B.)

The starting molecule BPA30EODMA (BPE-1300N from Shin Nakamura Chemical)is a bifunctional compound, the homopolymer of which is very flexible(Tg=−30° C. measured through differential scanning calorimetry).

Stiffening of the network is illustrated by the increasing values of E′(25° C.), E′ (100° C.) and Tg upon the introduction of methacrylic acid.From 50% of methacrylic acid, the obtained Tg is higher than 150° C.,which is particularly high for an acrylic thermo-hardened network.

The density of the solid material is relatively high, illustrating theintensity of interactions of the hydrogen link type.

Introducing methacrylic acid into the system limits the network wateruptake. However, introducing high rates of highly polar acidic functionshould result in an increased hydrophilic character. Such behaviourshows that acidic links strongly interact within the polymeric networkand are no longer available for interactions with water molecules fromthe outer environment.

COMPARATIVE EXAMPLE C2 AND EXAMPLE 5

The same procedure as in example 1 is used, but substituting theBPA30EODMA oligomer for a urethane diacrylate oligomer CN965 from CRAYVALLEY Corporation. As a comparison, said urethane diacrylate has beenpolymerized in the absence of acrylic acid. The compositions and resultsare given in table II hereinafter:

TABLE II C2 EX5 Polymerizable composition (liquid) Urethane acrylate (CN965) 100 60 AA 0 40 Release agent 0 0.5 UV absorber 0 0Photopolymerization primer 0.1 0.1 Solid polymerized material n_(e) (25°C.) 1.4922 1.5031 ν_(e) (25° C.) 55.2 54.5 Density — 1.23 E′ at 25° C.(MPa) — 1500 E′ at 100° C. (MPa) — 180 Tg (° C.) −30 125

COMPARATIVE EXAMPLE C3 AND EXAMPLES 6, 7 AND 8

Example 1 is repeated by substituting BPA30EODMA for PPG 400 DMA invarious proportions. The compositions and results are given in table IIIhereinafter.

TABLE III C3 EX6 EX7 EX8 Polymerizable composition (liquid) PPG400DMA(%) 100 80 70 40 AMA (%) — 20 30 60 Release agent (%) 0 0 0 0.1 UVabsorber (%) 0 0 0 0 Photopolymerization primer³ (%) 0.1 0.1 0.1 0.1n_(D) (25° C.) 1.450 1.44 1.45 1.45 Density 1.01 1.01 1.01 1.02Polymerized material (solid) n_(e) (25° C.) 1.48 1.492 1.494 — ν_(e)(25° C.) 45 57 55 — E′ at 25° C. (MPa) — 1,930 — — E′ at 100° C. (MPa) —210 — — Water uptake at 25° C. 0.15 0.13 — 0.13 Tg 20 107 — —

The results show that stiffening through methacrylic acid occurs even atlow methacrylic acid rates (20%) and that, on the other hand, thepresence of propoxy groups allows to reach extremely low water uptakerates.

COMPARATIVE EXAMPLE C4 AND EXAMPLES 9 TO 11

The same procedure as that previously implemented is carried out, butusing for component A a blend of BPA30EODMA and PPG 400 DMA oligomers.

The compositions as well as the obtained results are given in table IVhereinafter.

TABLE IV C4 EX9 EX10 EX11 Polymerizable composition (liquid) PPG 400 DMA50 40 30 25 BPA 30EODMA (%) 50 40 30 25 AMA — 20 40 50 Release agent (%)0 0 0 0.1 UV absorber (%) 0 0 0 0 Photopolymerization 0.1 0.1 0.1 0.1primer (%) n_(D) (25° C.) 1.471 1.465 1.458 1.453 Density 1.07 1.05 1.051.04 Polymerized material (solid) n_(e) (25° C.) — 1.503 — — ν_(e) (25°C.) — 52 — — E′ at 25° C. (MPa) — — 1,990 3,900 E′ at 100° C. (MPa) — —440 1,600 Tg (° C.) <20 — 147 163

COMPARATIVE EXAMPLE C5 AND EXAMPLES 12 AND 13

The same procedure as used previously is implemented but using forcomponent A a mixture of BPA30EODMA and dithiomethacrylate W oligomermade of a mixture of a first component represented by formula III (withn′ ranging from 1 to 10) and a second component represented by thefollowing formula:

in a respective first component/second component mass ratio of 65/35.The compositions and results are shown in table V hereinafter.

TABLE V C5 EX12 EX13 Polymerizable compositions (liquid)Dithiomethacrylate W (%) 50 40 30 BPA 30EODMA (%) 50 40 30 AMA — 20 40Release agent (%) 0 0 0 UV absorber (%) 0 0 0 Photopolymerization primer(%) 0.1 0.1 0.1 n_(D) (25° C.) 1.528 1.508 1.490 Density 1.16 1.13 1.10Polymerized material (solid) n_(e) (25° C.) 1.555 1.553 1.542 ν_(e) (25°C.) 42 44 48 E′ at 25° C. (MPa) — 916 3,840 E′ at 100° C. (MPa) — 851,140 Tg (° C.) <20 70 157

Stiffening by methacrylic acid is effective in all cases.

EXAMPLE 14

The above described examples are replicated using for component A amixture of BPA30EODMA and mono-2-(methacryloyloxy)ethyl phthalate (MAphthlate) from ALDRICH Corporation.

The proportions of the components of the composition and the results aregiven in table VI.

TABLE VI EX13 Polymerizable composition (liquid) BPA 30EODMA (%) 25 MAphthalate (%) 25 AMA (%) 50 Release agent (%) 0.1 UV absorber (%) 0Photopolymerization primer (%) 0.1 n_(D) (25° C.) 1.4698 Density 1.09Polymerized material (solid) n_(e) (25° C.) 1.5218 ν_(e) (25° C.) 44.4E′ at 25° C. (MPa) 2,070 E′ at 100° C. (Mpa) 130 Tg (° C.) 155 Wateruptake at 25° C./30 minutes (%) 1

EXAMPLE 15

Using the same procedure as previously described, spherical lenses havebeen manufactured with a −2 diopter power from the composition inexample 2.

The resulting lenses are subjected to a shock resistance trial using anincreasing energy ball drop (increasing the drop height up to break).

The results are shown in table VII hereinafter.

TABLE VII BPA30EODMA + 50% AMA (EX2) Mean centre thickness of the testedlenses 1.1 Number of lenses broken with 520 g (ball) 6 mass Mean breakenergy >5,800 mJ

Such results show that the compositions according to the invention allowfor high shock resistances to be obtained.

COMPARATIVE EXAMPLE C6

Example 2 from Patent Application WO 01/09205 is replicated in order toproduce spherical lenses with a −2 dioptre power.

Polymerizable composition Mass % SR 6440 P 52 * PLEX 6661-0 33 SR 423 A(isobornyl methacrylate from CRAY 15 VALLEY Corporation) * PLEX 6661-0from CRAY VALLEY Corporation has the following formula:

with R′₃ and R′₄ representing independently from each other H or CH₃.

The resulting lenses, with a −2 dioptre power and a centre thickness of1.1 mm, are subjected to a shock resistance trial, using the sameprotocol as in example 15.

Results

Number of lenses broken with 520 g (ball) mass 31 Mean break energy3,300 mJ

1. A radically polymerizable composition comprising: a first component Acomprising at least an oligomer having at least two radicallypolymerizable functions, which, when polymerized, form a homopolymer ofwhich has a glass transition temperature (Tg) lower than 50° C., such acomponent being able to result through polymerization in a (co)polymerhaving a glass transition temperature (Tg) equal to or lower than 50°C., said oligomer accounting for more than 15%, of the total weight ofthe polymerizable monomers present in the composition; and a secondcomponent B comprising at least a (meth)acrylic monomer having at leastone H link promoting group, such a (meth)acrylic monomer accounting forat least 15% of the total weight of the polymerizable monomers andoligomers present in the composition when such a monomer is amethacrylic monomer and at least 35% of the total weight of suchpolymerizable monomers and oligomers present in the composition whensuch a monomer is an acrylic monomer and represented by the formula:

wherein R represents H or CH3; Z represents a single covalent link or adivalent spacer group; and Z′ is the H link promoting group selectedfrom: —COOH, —CONHR′, —NHCONHR″, —NHCOOR″′, —NHCOSR^(iv) and—NHR^(v)wherein R, R″, R″′, R^(iv) and R^(v) represent, independently from eachother, H or a C₁-C₁₀ alkyl group or a C₆-C₁₀ aryl group.
 2. Thecomposition of claim 1, wherein the oligomer of the first component A isa difunctional oligomer.
 3. The composition of claim 2, wherein theoligomer is a di(meth)acrylate.
 4. The composition of claim 2, whereinthe oligomer is a dim ethacrylate.
 5. The composition of claim 1,wherein the oligomer has a number average molecular mass Mn ranging from100 to 5,000 g.mol-1.
 6. The composition of claim 5, wherein theoligomer has a number average molecular mass Mn ranging from 200 to 4000g.mol-1.
 7. The composition of claim 6, wherein the oligomer has anumber average molecular mass Mn ranging from 300 to 2,000 g.mol-1. 8.The composition of claim 1, wherein the copolymer has a glass transitiontemperature (Tg) equal to or lower than 0° C.
 9. The composition ofclaim 8, wherein the copolymer has a glass transition temperature (Tg)ranging from −50° C. to -10° C.
 10. The composition of claim 1, whereinsaid oligomer of component A accounts for at least 20% of the totalweight of polymerizable monomers present in the composition.
 11. Thecomposition of claim 1, wherein the oligomer is poly(alkylene)glycoldi(meth)acrylates, polyethoxy bisphenol-A dimethacrylates,dithio(meth)acrylates or urethane di(meth)acrylate.
 12. The compositionof claim 1, wherein the oligomer is poly(ethyleneglycol) dimethacrylatesand poly(propyleneglycol) dimethacrylates.
 13. The composition of claim12, wherein the oligomer is a poly(propyleneglycol) dimethacrylate witha number average molecular mass of approximately 530 g.mol-1.
 14. Thecomposition of claim 1, wherein the first component A comprisesadditionally at least one other comonomer, being not an oligomer,comprising at least one radically polymerizable function.
 15. Thecomposition of claim 1, wherein the radically polymerizable function isa (meth)acrylate function.
 16. The composition of claim 1, wherein the Hlink promoting (meth)acrylic monomer is a monofunctional monomer. 17.The composition of claim 16, wherein the H link promoting (meth)acrylicmonomer is acrylic acid, methacrylic acid, mono-2-(methacryloyloxy)ethylsuccinate or mono-2-(methacryloyloxy)ethyl phthalate.
 18. Thecomposition of claim 1, wherein the Z is a divalent hydrocarbon chain.19. The composition of claim 18, wherein the divalent hydrocarbon chainis interrupted by one or more heteroatom or by one or more groups asfollows:

by one or more divalent groups of formula: —NH—CO—NH—; —NH—COO—;—NHCOS—; or —NHCSS—.
 20. The composition of claim 19, wherein the one ormore heteroatom is O, S and N.
 21. The composition of claim 18, whereinthe hydrocarbon chain comprises from ito 1 to 10 carbon atoms.
 22. Thecomposition of claim 21, wherein the hydrocarbon chain comprises from 1to 6 carbon atoms.
 23. The composition of claim 1, wherein the Z is apolyether, polyester, polyurethane, polyurea or polyurethane group. 24.The composition of claim 1, wherein the alkyl group is an aliphatic orcycloaliphatic group.
 25. The composition of claim 1, wherein thealiphatic group is —CH3.
 26. The composition of claim 1, wherein Z′ isthe —COOH group.
 27. The composition of claim 1, wherein R is CH3. 28.The composition of claim 1, wherein it additionally comprises aneffective amount of at least one thermal and/or photochemicalpolymerization primer.
 29. A product resulting from the thermal and/orphotochemical polymerization of a composition comprising: a firstcomponent A comprising at least an oligomer having at least tworadically polymerizable functions, which, when polymerized, form ahomopolymer of which has a glass transition temperature (Tg) lower than50° C., such a component being able to result through polymerization ina (co)polymer having a glass transition temperature (Tg) equal to orlower than 50° C., said oligomer accounting for more than 15%, of thetotal weight of the polymerizable monomers present in the composition;and a second component B comprising at least a (meth)acrylic monomerhaving at least one H link promoting group, such a (meth)acrylic monomeraccounting for at least 15% of the total weight of the polymerizablemonomers and oligomers present in the composition when such a monomer isa methacrylic monomer and at least 35% of the total weight of suchpolymerizable monomers and oligomers present in the composition whensuch a monomer is an acrylic monomer and represented by the formula:

wherein R represents H or CH3 Z represents a single covalent link or adivalent spacer group; and Z′ is the H link promoting group selectedfrom: —COOH, —CONHR′, —NHCONHR″, —NHCOOR″′, —NHCOSR^(iv) and—NHR^(v)wherein R, R″, R″′, R^(iv) and R^(v) represent, independently from eachother, H or a C₁-C₁₀ alkyl group or a C₆-C₁₀ aryl group.
 30. The productof claim 29, wherein it has an elastic modulus E' at 100° C. of at least40 MPa.
 31. The product of claim 30, wherein it has an elastic modulusE' at 100° C. of at least 100 MPa.
 32. The product of claim 31, whereinit has an elastic modulus E' at 100° C. of at least 120 MPa.
 33. Theproduct of claim 29, further defined as an optical lens.
 34. The productof claim 29, further defined as an ophthalmic, finished orsemi-finished, lens.
 35. The product of claim 29, wherein the copolymerhas a glass transition temperature (Tg) equal to or lower than 0° C. 36.The product of claim 29, wherein the copolymer has a glass transitiontemperature (Tg) ranging from −50° C. to −10° C.
 37. The product ofclaim 29, wherein said oligomer of component A accounting for at least20% of the total weight of polymerizable monomers present in thecomposition.